Spool



Bday 18, 1926.

H. H. DOEHLER ET A1.

sPooL Filed July 1, 1925 l l lllgll/ nvVENToRS Her/nan H. 0o eA/er ATTORNEYJ Aelectroniagnetic coils, for example.

Patented i May 18, 1926.

UNITED STATES PATENT OFFICE.

HERMAN H. DOEHLER AND LOUIS H. MORIN,- OE NEW YORK, N. Y., A-SSIGNORS T0DOEHLER DIE-CASTING CO., A CORPORATION OF NEW YORK.

SPOOL.

Application led July 1, 1925. Serial No. 40,738.

Metallic. die-cast spools have to a large extent replaced wooden spoolsfor holding smaller sizes of wire such as is wound into These spoolshave an axial bore of a suitable size to fit upon a spindle, while theoutside diameter of the spools must be considerably larger in order thatthe first layers of the wire will not be wound so small as to make thewire wavy and hard to rewind. For the sake of lightness and economy inmetal, the metal spools are made in the form of relatively thin shellswith an axial bearing tube mounted within them and concentrically spacedfrom the spool body. The mounting of this axial tube presents a problemto which our invention is directed.

p The metallic spools heretofore commonly used have an integral bearingfor the tube at one end, and at the other end a seat for a disc having acentral hole forming a bearing for the opposite end of the tube. In thistype of spool the tube is assembled in the spool after the spool body iscast, the

r ends of the tube being expanded outside the two bearings to hold itagainst longitudinal movement, and the parts are suitably shaped to lockthe tube to the spool body against relative angular movement. .Thepulling of theL core requires that one of the end bearings be removable.

In accordance with our invention the tube isv permanently united to thespool body through a single integral web which may be disposed anywherewithin the spool and which'so tightly embraces the tube as to hold itagainst any relative movement.

vl'ractically this is accomplished by casting the spool upon the tube asan insert. The web may be made quite thin since it is subjectedtorelatively little strain and its embracing portion may be elongated tothe extent necessary to effect the requisite rigidity. The embracedportion of the tube may be knurled the better to secure the partstogether, although it will be found that ordinarily this is unnecessary.

In the drawings we have shown two embodiments of our invention differingprimarily in the location ofthe attaching web, Figures 1 and 2 being,respectively, a longitudinal section and a left end view of one form,and Figures 3 and 4 being corresponding views of another lform.

In the form of spool `shown in Figures 1 and 2, the attaching web is atthe extreme end of the spool. The body 1 is a relatively thin shelledtube of die-cast metal having the usual flanged ends 2 and 3. The "axialbearing tube 4 is composed of suitfa'ble hard metal, such as steel, andis shownas somewhat shorter than the over-all length of the spool. Thistube 4 is materially smaller than the shell 1, and consequently there isa considerable annular space 5 between the tube and the shell. A web 6,which is integral with the shell 1, couples the tube and Nshell, thisbeing accomplished, as above suggested, by casting the spool directlyupon the tube. In the construction of Figures 1 and 2, this web 6 is, asabove stated, at the 4extreme end 'of the shell 1, and a correspondingend of the tube 4 has its external surface knurled, while the embracingportion of the web is somewhat elongated. Due to the dilerentco-eliicients of expansionand contraction possessed by the metals ofthe'shell and of the tube, the webl embraces t-he tube very tightly whenthe casting is -cooled and forms a rigid connection between the twoparts. The opposite end ot' the casting is left open for core-pullingpurpose. A small'hole 7 may be provided in the web 6 for the receptionof a driving IVe have/found that the axial tube is' ordinarily heldsufficiently rigidly for all practical purposes when the web is locatedat the extreme end, as in the construction of Figures 1 and 2. However,if preferred, the web may be centrally disposed, as shown in Figures 3and 4. In this form, the weby boss at one point to accommodate the.driving hole 7. y

It is obvious that various modifications may be made 1n the constructionshown in t-he drawings yand above particularly .der`

scribed and illustrated within the principle and scope of our invention.

casting and, in this instance, the shell is. thickened or provided with.a longitudinal We claim:

l. A metallic hollow spool including an axial tube of metal harder thanthe spool body and of substantially smaller diameter thanl the hollow'interior of the spool, and an integral, transverse tube-gripping portionWithin the spool fitting around the tube for a small part of the tubeslength with sufficient tightness to hold the tube positively againstrela-tive longitudinal or angular movement.

2. A hollow spool .of die-casting metal with an axial tube of hardermetal substan tally smaller in diameter Ithan the hollow interior of thespool andhaving an external roughened portlon, and an integral webWithin the spool gripping the tube abqut the. roughened portionsufficiently tightly to prevent relative longitudinalor angular lmovement.

In witness whereof, We hereunto subscribe our signatures.

HERMAN H. DOEHLER. LOUIS H. MORIN.

